SmallSats, Iodine Propulsion Technology, Applications to Low-Cost Lunar Missions, and the iodine Satellite (iSAT) Project.

Presented to Lunar Exploration Analysis Group (LEAG) October 23, 2014 The SmallSat Market SmallSat Applications – USASMDC / ARSTRAT

Low Cost • Per-Unit Cost Very Low • Enables Affordable Satellite Constellations • Minimal Personnel and Logistics Tail • Frequent Technology Refresh Survivability • Fly Above Threats and Crowded Airspace • Rapid Augmentation and Reconstitution • Very Small Target Responsiveness • Short-Notice Deployment • Tasked from Theater • Persistent and Globally Available • Can Adapt to the Threat

DISTRIBUTION A. Approved for public release; 24 July 2013 Release Number 3105 Why Iodine?

• Today’s SmallSats have limited propulsion capability and most spacecraft have none • The State of the Art is cold gas propulsion providing 10s of m/s ∆V • No solutions exist for significant altitude or plane change, or de-orbit from high altitude • SmallSat secondary payloads have significant constraints • No hazardous propellants allowed • Limited stored energy allowed • Limited volume available • Indefinite quiescent waiting for launch integration

• Iodine is uniquely suited for SmallSat applications • Iodine electric propulsion provides the high ISP * Density (i.e. ∆V per unit volume) • 1U of iodine on a 12U vehicle can provide more than 5 km/s ∆V • Enables transfer to high value operations orbits • Enables constellation deployment from a single launch • Enables de-orbit from high altitude deployment (ODAR Compliance) • Iodine enables > 10km/s for ESPA Class Spacecraft • GTO deployment to GEO, Lunar Orbits, Near Earth Asteroids, Mars and Venus • Reduces launch access by 90% • Reduces mission life cycle cost by 30 – 80% • Iodine is a solid at ambient conditions, can launch unpressurized and sit quiescent indefinitely

• The technology leverages high heritage xenon Hall systems • All systems currently at TRL 5 with maturation funded to achieve TRL 6 in FY16 • The iSAT System is planned for launch readiness in early 2017 Iodine vs. Alternatives

Propellant Storage Density Boiling Point, oC Melting Point, oC Vapor Pressure @ 20oC Xe (SOA) 1.6 g/cm3 -108.1 oC -111.8 oC Supercritical (>15MPa) Iodine 4.9 g/cm3 184.3 oC 113.7 oC 40 Pa (0.0004 atm) Bismuth 9.8 g/cm3 1,564 oC 271.4 oC Solid Magnesium 1.74 g/cm3 1,091 oC 650 oC Solid

Iodine has unique characteristics well suited for mission application Microsatellite Advantages

Primary mission advantages are due to 1) Increased ISP * Density 2) Low storage pressure

Microsatellites are extremely volume constrained Geocentric MicroSat Application

Large increase in demand for MicroSat constellations and responsive space capabilities. - The 12U with 5kg of iodine can perform 4km/s ∆V - 20,000km altitude change - 30o inclination change from LEO - 80o inclination change from GEO - Larger spacecraft can perform even greater ∆V

Iodine in enabling for rapidly growing spacecraft market. Interplanetary MicroSat

NASA is pursing interplanetary MicroSat missions - INSPIRE selected as first interplanetary CubeSat – no propulsion - NASA HEOMD AES funding NEA Scout – solar sail propulsion - NASA HEOMD AES funding Lunar Flashlight – solar sail propulsion - High pressure and hazardous propellants are not allowed

Iodine on an interplanetary CubeSat can provide ~2.5km/s of ∆V - Challenges with communications and attitude control over geocentric spacecraft - Enables Lunar orbiter, asteroid flyby and rendezvous missions for <$20M life cycle cost - Enables secondary missions via primary host deployment - Outer planet moons - Constellations

Iodine enables high ∆V interplanetary propulsion ESPA Class Mission Concept – Lunar Orbiter

Detailed ACO Study for Lunar Orbiter with “Discovery” science payload - Deployment from GTO - Iodine enabled 100x5km orbit station-keeping - Total life cycle cost ~$150M - Leveraged 2x BHT-600-I Thrusters

Iodine / Electric Propulsion enables high value lunar orbiter science despite multiple previous lunar missions. Orbit Transfer Vehicles

The direct replacement of xenon for iodine will significantly increase ∆V capability or enable additional payloads on the carrier vehicle.

Iodine OTV can deliver large number of SmallSats / CubeSats from GTO to a range of Lunar orbits. Mid-Term Iodine Objectives

Multiple Studies Completed on Enabling Applications: 1) 200 W Iodine is enabling for NanoSats (1-10kg) and MicroSats (10-100kg) - Iodine properties are ideal for secondary payloads - Benign propellant, quiescent until heated - Launches and stores unpressurized 3 3 - High density ~6g/cm and high Density – ISP ~ 8,000 g-s/cm - Xe ~3,000 g-s/cm3, Solid Motor ~500 g-s/cm3, Cold Gas ~150 g-s/cm3 - Enables orbit maneuverability (plane change and altitude change) - Enables spacecraft deorbit 2) 200W – 600W Iodine enables very high ∆V for ESPA class (180kg) spacecraft - Can provide ~10km/s ∆V - More than 2x the Xenon ∆V capability (Volume limited) - Enables GTO to Asteroids, Mars and Venus (Iodine and Xenon can both go to the moon) 3) 600W Iodine Enables “Discovery Class” Science Instruments for ESPA Grande class (300kg) spacecraft - Volume limitations require high density propellant - 3x – 5x reduction in total mission cost - New class of HEOMD and SMD missions 4) 600W – 1.5KW Class Iodine Enables Orbit Maneuvering Systems - Iodine based ESPA OMS can enable high ∆V using the volume within the ESPA ring - Can enable additional payloads over Xenon from GTO to GEO - Can enable independent payload delivery to various Mars orbits

The technology can be enabling for a wide range of future commercial, academic, DoD and NASA HEOMD and SMD missions. iSAT Mission Concept Overview

The iSAT Project is the maturation of iodine Hall technology to enable high ∆V primary propulsion for NanoSats (1-10kg), MicroSats (10-100kg) and MiniSats (100-500kg) with the culmination of a technology flight demonstration. - NASA Glenn is leading the technology development and is the flight propulsion system lead - Busek delivering the qualification and flight system hardware - NASA MSFC is leading the flight system development and operations

The iSAT Project launches a small spacecraft into low-Earth orbit to: - Validate system performance in space - Demonstrate high ∆V primary propulsion - Reduce risk for future higher class iodine missions - Demonstrate new power system technology for SmallSats - Demonstrate new class of thermal control for SmallSats - Perform secondary science phase with contributed payload - Increase expectation of follow-on SMD and AF missions - Demonstrate SmallSat Deorbit - Validate iodine spacecraft interactions / efficacy

High value mission for SmallSats and for future higher-class mission leveraging iodine propulsion advantages. iSAT Project Overview Mission Justification

There is an emerging and rapidly growing market for SmallSats - SmallSats are significantly limited by primary propulsion - Desire to transfer to higher value science / operations orbit and responsive space - Desire to extend mission life / perform drag make-up - Requirement to deorbit within 25 years of end-of-mission Limitations on SmallSats limit primary propulsion options - Requirements imposed by nature of secondary payloads - Limitations for volume, mass and power - Limitations on hazardous and stored energy from propellants - Limitations for high pressure systems - Systems must sit quiescent for unknown periods before integration with primary

Why perform flight validation? - Reduce risk of implementation of iodine for future higher class missions - Gain experience with condensable propellant spacecraft interactions - Reduce risk of custom support systems - Power generation, storage and distribution - Thermal control - Cost effective risk reduction before maturing higher power systems iSAT Project Overview Mission Justification

 200W NanoSat infusion near-term with low entry cost and lower risk  Short mission durations, low throughput requirement, simple propellant management  Engineering / material changes and validation, valve wetting surfaces and seals  Demonstrates enabling technology, demonstrates high spacecraft power density

 Additional high payoff for higher power / high payoff mission infusion  Critical Technology Gaps and Risks Remain  Propellant flow rate and metering is critical to achieve required performance  Large propellant management, potentially conformal tanks  Uniform / efficient heating and propellant management critical  Wear testing >1000hrs for both thrusters and cathodes  Additional material compatibility testing  Spacecraft / plume interactions testing and analyses  Sputter erosion data, erosion modeling and lifetime analyses

Critical gaps remain for efficient propellant heating, transport and metering in a relevant environment in addition to long duration test data and analyses required for mid-term mission infusion. iSAT Project Overview Stakeholder Expectations

The iSAT project is supported by a wide range of customers including: - MSFC Technology Investment Program (TIP) - MSFC Center Strategic Development Steering Group (CSDSG) - Office of the Chief Technologist (OCT) - Advanced Exploration Systems (AES) Program - Game Changing Development (GCD) Program - NASA Engineering and Safety Center (NESC) - Air Force: AFRL, ORS and SMC - Small Business Innovative Research (SBIR) Program

Additional stakeholders include: - NASA Glenn to transition a new Electric Propulsion technology to flight - NASA MSFC to provide flight system development experience to young engineers - SmallSat Program to enable new capabilities for future SmallSat missions - Future commercial contractors (ULA, Northrop Grumman, NanoRacks, etc.) - Science Mission Directorate (SMD) - Busek, the Small Business with the IP for the iodine Hall system - Far-term users for high power iodine Hall systems

Primary Customer: - STMD: SmallSat Technology Program iSAT Project Overview Mission Justification  High applicability at a range of power levels  200W System: (10-20kg S/C) – LEO maneuverability, constellations and de-orbit – Launch <$1M  600W+ System (100 – 300kg S/C) – New class of interplanetary missions – Launch < $20M

2013 2014 2015 2016 2017 2018 2019 2020 2021 2022

Iodine Technology 200W 600W >1kW Development

Flight Demonstration

200W TDM 600-1200W $10M Class $100M Class

Mission Infusion Earth Science and PSD, HEOMD and DoD, Commercial Commercial High near-term flight infusion potential 16 16 iSAT Project Overview Mission Justification – Launch Vehicle Savings

Secondary SmallSats can reduce launch costs by >90%.

Iodine enables interplanetary SmallSats from GTO.

17 Mission ConOps

LAUNCH DEPOLOY

•Ride-share launch opportunity •Deployable solar arrays for power production •Most likely to sun-synch orbit •Deployable thrust assembly to support management of internal thermal environment

CHECK OUT OPERATIONS DEORBIT

•Evaluate tip-off moments •Support tech demo through inclination •Natural drag interaction will result in change and perigee lowering operations deorbit after perigee is lowered •Arrest initial rotation with magnetic torquers •See next chart for timeline details 12U LEO Design Reference Mission

iSAT Mass Estimation List (MEL) Basic Mass (kg) MGA (%) MGA (kg) Predicted Mass (kg) 1.0 Structures 1.601 30% 0.480 2.081 2.0 Mechanisms 0.100 30% 0.030 0.130 3.0 Thermal 0.334 30% 0.100 0.434 4.0 Power 2.052 30% 0.616 2.668 5.0 Guidance Navigation & Control (GN&C) 1.518 10% 0.152 1.670 6.0 Communications 0.090 6.00% 0.005 0.095 7.0 Command and Data Handling (C&DH) 0.324 16% 0.053 0.377 8.0 Propulsion 3.846 25% 0.965 4.811 Dry Mass 9.864 24% 2.401 12.265 9.0 Payload 6.000 0% 0.000 6.000 10.0 Non-Propellant Fluids 0.000 0% 0.000 0.000 Inert Mass 15.864 15% 2.401 18.265 11.0 Propellant (Solid Iodine) 0.720 0.000 0.720 iSAT Total Mass 16.584 2.401 18.985

12U LEO option is the only preliminary concept with margin; lowest risk and selected as the Baseline. System Architecture

Propulsion System Payload Attitude Control System Pressure Camera Torquers Fuel Transducer (2) Tank Payload Valves

Cathode Momentum Thruster Wheels

Attitude Determination System

Avionics System GPS Unit Avionics Cards

Star Tracker Accelerometer PPU IMU 20 Sun Sensor Development Schedule

The iSAT Project is on an aggressive schedule for FY17 launch. Interplanetary ConOps

• Interplanetary mission will require entirely different con-ops than the LEO missions • Assume EM-1 Launch, Deployment will occur at +C3 • Rotation damping and initial orientation will be achieved through the use of reaction wheels and cold-gas thrusters • Flight orientation and thruster duty cycle will be dependent on destination – Will most likely require periods of thrust followed by periods of charging – Destination (and resulting trajectory) will determine whether charging can occur without spacecraft rotation • Science operations will be dependent on destination

Though not the iSAT Baseline Mission: Iodine Hall for EM-1 to lunar orbit under development. Propulsion

BHT-200-I Thruster: - Heritage to TacSat-2 - Most studied thruster since SPT-100 - Material changes for iodine compatibility

Cathode: LaB6 and Electric Cathodes under consideration - Minimize power requirements - Both successfully operated on iodine

Compact PPU: - 3rd PPU iteration ongoing - Based on BPU-600 - 80% Mass reduction - 90% Volume reduction

Feed System & DCIU Education and Public Outreach

Large number of outreach events NASA Mission Needs  SmallSats  Technology Gaps  iSAT NASA Mission Needs  Propulsion  Electric Propulsion  Iodine

E&PO is a large part of the iSAT project. Progress to Date

Successfully Completed MCR – February 28th Table Top SRR – July 8, 2014

PDR and System Demonstration – November 13, 2014

Hardware Status: - BB Battery delivered – February 20, 2014 - BB EPS delivered – March 7, 2014 - BB DCIU delivered – March 27, 2014 - EM PPU Delivered – April 1, 2014 - EM Battery delivered – April 4, 2014 - EM Cathodes delivered – April 9, 2014 (two to GRC) - EM Flight computer delivered – April 14, 2014 - EM Thruster Delivered – June 6, 2014 - Initial DCIU / Feed System Test – June 12, 2014 - Material testing initiated - Ongoing - Integrated propulsion system check-out - Ongoing

Significant hardware rich investments to reduce risk and simply integrate and fly as a technology demonstration mission. Near-term Events

Near-term system performance characterization at NASA. Closing Remarks

 SmallSats hold significant potential for future low cost high value missions  Propulsion remains a key limiting capability for SmallSats that Iodine can address - High ISP * Density for volume constrained spacecraft - Indefinite quiescence, unpressurized and non-hazardous as a secondary payload  Iodine enables MicroSat and SmallSat maneuverability - Enables transfer into high value orbits, constellation deployment and deorbit  Iodine may enable a new class of planetary and exploration class missions - Enables GTO launched secondary spacecraft to transit to the moon, asteroids, and other interplanetary destinations for ~$150M full life cycle cost including the launch  ESPA based OTVs are also volume constrained and a shift from xenon to iodine can significantly increase the transfer vehicle ∆V capability including transfers from GTO to a range of Lunar Orbits  The iSAT project is a fast pace high value iodine Hall technology demonstration mission - Partnership with NASA GRC and NASA MSFC with industry partner – Busek  The iSAT mission is an approved project with PDR in November of 2014 and is targeting a flight opportunity in FY17. Questions? Acknowledgments

Resources were provided for this work in part by the MSFC Center Innovation Fund from the Office of the Chief Technologist as part of MSFC Technology Investment Program, the MSFC Center Strategic Development Steering Group, MSFC Technical Excellence funding under the Office of the Chief Engineer, the Air Force Operationally Responsive Space Office, the Advanced In-Space Propulsion project under the Space Technology Mission Directorate, the NASA Engineering and Safety Center, with support from NASA’s Science Mission Directorate under Directed Research and Technology, Busek Co., the NASA Office of Education and the NASA Small Business and Innovative Research Program. The authors wish to thank the entire iSAT team for their input and progress to date.